There are human activities in which both sides can win. War is not one of them. Either Ukraine wins this war or Russia does. Ukraine’s former foreign minister Dmytro Kuleba says bluntly that unless the current trajectory is changed, “we will lose this war”.

To be clear: this is still avoidable. Suppose the roughly four-fifths of Ukrainian territory still controlled by Kyiv gets military commitments from the west strong enough to deter any further Russian advances, secure large-scale investment in economic reconstruction, encourage Ukrainians to return from abroad to rebuild their country, and allow for stable, pro-European politics and reform. In five years, the country joins the EU, and then, under a new US administration, starts the process of entering Nato. Most of Ukraine becomes a sovereign, independent, free country, firmly anchored in the west.

The loss of a large amount of territory, the suffering of at least 3.5 million Ukrainians living under Russian occupation and the toll of dead, maimed and traumatised would amount to a terrible cost. This would not be the complete victory Ukrainians have hoped for and deserve; but it would still be a victory for Ukraine and a historic defeat for Russia. A majority of Ukrainians could come to see it as such. In polling the Kyiv International Institute of Sociology (KIIS) has shared with me in advance, Ukrainians are asked if to end the war they could (albeit with difficulty) accept the combination of economic reconstruction and EU and Nato membership for the current territory. In just the past six months, the proportion saying yes has jumped from 47% to 64%.

However, to get to this outcome with Donald Trump in the White House would require a European coalition-of-the-willing to make security commitments of a size and boldness not seen so far. There’s a growing understanding of this among European leaders, but the democratic politics in most European countries are miles away from empowering them to do it. To try to persuade Europeans to support the necessary policies, but also to understand the consequences if – as seems most likely – they don’t do so in time, the question we have to ask is: what if Russia wins?

If Russia wins, we should realistically expect the following consequences for Ukraine, Europe, the United States and world peace. Ukraine would be defeated, divided, demoralised and depopulated. The money would not come in to reconstruct the country; instead, another wave of people would leave it. The politics would become rancorous, with a strong anti-western trend. New possibilities for Russian disinformation and political destabilisation would emerge. Necessary reforms would stall, and hence also progress towards EU membership.

Europe as a whole would see an escalation of the hybrid war that Russia is already waging against it, still largely unnoticed by most blithely Christmas-shopping west Europeans. Not a week passes without some incident: a Russian destroyer fires a flare at a German military helicopter; there are exploding DHL packages, sabotage on the French railways, an arson attack on a Ukrainian-owned business in east London; undersea cables in the Baltic Sea are cut; there’s a credible death threat to a top German arms manufacturer. Not all can definitely be traced back to Moscow, but many can.

Full spectrum hybrid warfare includes election interference. In Georgia, the election was rigged. In the Moldovan EU referendum, about 9% of the votes were directly bought by Russia, according to the president, Maia Sandu. In Romania, the first round of the presidential election will be re-run, because a court found large-scale violation of campaigning rules on TikTok. “Ah, that’s eastern Europe!” cries the complacent Christmas shopper in Madrid, Rome or Düsseldorf. But the head of Germany’s domestic security service recently warned that Russia will try to interfere in next February’s German general election, which is hardly marginal to the future of Europe.

This week we saw Vladimir Putin again supremely confident in his annual end-of-year marathon press conference cum Call-the-Tsar phone-in, despite the recent Ukrainian assassination of his WMD general. His is now a war economy, dependent on military production for sustaining growth, and a dictatorship defined by confrontation with the west. It would be beyond naive to hope that diplomacy can achieve some magical moment when Putin’s Russia will suddenly become “satisfied” with an outcome in Ukraine, and return to peacetime business as usual. When Nato planners say we should be ready for possible Russian aggression against Nato territory by 2029, they are not simply peddling horror stories so as to increase military budgets.

Maga voters in the United States may say “well, what’s all that to us? You Europeans look after yourselves! We have to worry about China”. But Russia is now working more closely than ever with China, North Korea and Iran. Putin may be indicted by the international criminal court, but he still travels half the world as a welcome guest. He himself has talked of a new “global majority” and “the formation of a completely new world order”. In that new order, war and territorial conquest are entirely acceptable instruments of policy, on a continuum with poisoning, sabotage, disinformation and election interference. Victory for Russia in Ukraine will encourage China to step up its pressure on Taiwan and North Korea its needling of South Korea.

That brings us to the most serious consequence of all: nuclear proliferation. Remember that Ukraine voluntarily gave up its nuclear weapons in 1994, in return for security assurances from the US, the UK and Russia – and then got hammered by one of the powers that promised it security. In the latest KIIS polling, 73% of Ukrainians support Ukraine “restoring nuclear weapons”. Remarkably, 46% say they would do so even if the west imposed sanctions and stopped aid. In effect, Ukrainians are saying to the west: if you won’t defend us, we’ll [expletive deleted] do it ourselves. On recent visits to Ukraine I’ve been told several times, “It’s Nato or nukes!” But this is not just about Ukraine. Vulnerable countries around the world, also looking at what is happening in the Middle East, will draw the same conclusion. The more countries – and possibly non-state actors – acquire nuclear weapons, the more certain it is that one day they will be used.

In the German election, Chancellor Olaf Scholz has been shamelessly and shamefully trying to exploit the fear of nuclear war for electoral advantage over his chief rival, the Christian Democrat Friedrich Merz. In fact, it is precisely the consequences of the west’s self-deterrence for fear of Russian nuclear escalation in Ukraine, personified by Scholz and skilfully exploited by Putin, that are increasing the likelihood of nuclear proliferation and therefore the long-term risk of nuclear war.

The conclusion is clear, and depressingly familiar. European democracies’ reluctance to pay a high price now means that the world will pay an even higher price later.

  • Timothy Garton Ash is a Guardian columnist

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